This project remains active principally to complete work describing melanocyte development and survival in a mouse model of the human deafness-pigmentation syndrome Waardenburg syndrome. In this study, the otic phenotype of this mouse model was studied. These mice exhibit a hearing deficit due to loss of melanocytes in the ear during the first several days of post-natal life. These results help to explain an important disparity between the severe otic pigmentary phenotype and the relatively mild cutaneous pigmentary phenotypes observed in individuals with the inherited developmental pigmentary disorders Waardenburg syndrome and Tietz syndrome. This work is currently under review at Pigment Cell & Melanoma Research.